Meso- and thermo-Mediterranean xerophile, short-grass perennial grasslands and therophyte communities of oligotrophic soils on base-rich substrates of Spain, southern France, the large west Mediterranean islands, Italy and Mediterranean North Africa.
Open grasslands of the coussous still covering vast but dwindling expanses of the Crau (southern France) a fossil delta of the Durance, with Brachypodium retusum, Stipa capillata, Dichanthium ischaemum, Elymus caput-medusae, Thymus vulgaris, Bellis sylvestris, Asphodelus fistulosus, Euphorbia seguierana, Linum gallicum, Salvia multifida, Bufonia macrosperma; they support a fauna of exceptional originality.